Clinical Research Directory

Effects of Caffeine Ingestion on Morning Cognitive and Muscle Repeated Sprint Performance in Males

Athletes often compete in the morning when they are biologically weaker; normally in competition heats or quarterfinals to qualify for the finals scheduled in the evening. Some athletes may even choose to perform at submaximal levels in these qualifying rounds, especially when they are expected to perform multiple times in the same day (such as weightlifting at the Olympic Games). Gross muscular performance such as power output or force production is greater in the evening than the morning (\~3-14% variation). Similarly, time-trial performance and repeated sprint performance (RSP; a good measure of performance in team sport) is \~3 and 5 % greater in the evening than the morning. The reason for this daily variation in performance is attributed to central factors (such as the body clock), as well as motivational and peripheral factors, including higher core and muscle temperatures in the evening compared to the morning. The body clock located within the anterior hypothalamus consists of a group of neurons known as suprachiasmatic nuclei, which are responsible for controlling the rhythm of core temperature. This 'master clock' has an endogenous period (\~24.2 h) slightly longer than the 24-h solar day; therefore, must be entrained by time cues (zeitgebers) to remain in sync with the environment, of these the light-dark cycle is the most powerful in humans. The most efficient nutritional ergogenic is caffeine. Recently caffeine has been investigated to reduce the negative influence of diurnal variations on repeated-sprint ability test (10 × 6 s cycle sprints, with 30 s of rest) at 60 min after ingestion of either 5 mg·kg-1 or placebo. A recent study reported that caffeine supplementation did not prevent the reduction in performance in the morning. However, placebo effect can be 3-5% and hence the use of a No-pill condition would ensure that any placebo effect is accounted for and that the true potential effect of caffeine can be established. To the best of our knowledge, no study has yet investigated a) caffeine (300 mg), NoPill or Placebo (300 mg dextrose) effects on cognitive and physiological morning performance.

Effects of Caffeine Ingestion on Morning Cognitive and 4-km Time Trial Performance in Males

Athletes often compete in the morning when they are biologically weaker; normally in competition heats or quarterfinals to qualify for the finals scheduled in the evening. Some athletes may even choose to perform at submaximal levels in these qualifying rounds, especially when they are expected to perform multiple times in the same day (such as weightlifting at the Olympic Games). Gross muscular performance such as power output or force production is greater in the evening than the morning (\~3-14% variation). Similarly, time-trial performance and repeated sprint performance (RSP; a good measure of performance in team sport) is \~3 and 5 % greater in the evening than the morning. The reason for this daily variation in performance is attributed to central factors (such as the body clock), as well as motivational and peripheral factors, including higher core and muscle temperatures in the evening compared to the morning. The body clock located within the anterior hypothalamus consists of a group of neurons known as suprachiasmatic nuclei, which are responsible for controlling the rhythm of core temperature. The most efficient nutritional ergogenic is caffeine. Recently caffeine has been investigated to reduce the negative influence of diurnal variations on repeated-sprint ability test (10 × 6 s cycle sprints, with 30 s of rest) at 60 min after ingestion of either 5 mg·kg-1 or placebo. Lopes-Silva et al. (2019) reported that caffeine supplementation did not prevent the reduction in performance in the morning. However, placebo effect can be 3-5% and hence the use of a No-pill condition would ensure that any placebo effect is accounted for and that the true potential effect of caffeine can be established. To the best of our knowledge, no study has yet investigated caffeine (CAFF), NoPill (NOPILL) or Placebo (PLAC) effects on cognitive and 4-km time-trial (TT) performance. As a diurnal variation in 4-km TT has been widely reported in a similar population. The aim of the present study is to investigate if ingesting caffeine on the day of the morning test, to improve performance.

What is the Role of Type III/IV Muscle Afferents in Airway Resistance and Thermoregulatory Responses to Exercise?

Exercise places serious demands on the body. These demands are fundamentally caused by increases in oxygen demand and the consequent increase in body temperature. These demands are met by several physiological responses, including increases in heart rate, blood pressure, breathing and blood flow. These responses must be proportional to the increase in demand and some signal must relay information from the muscle to the brain. Group III/IV afferents do just this. They relay information about the muscle (movement, temperature, acidity, etc.) up to the brain so that appropriate responses are mounted. There is strong evidence in animals that group III/IV afferents play a key role in making breathing easier (decreasing airway resistance) and initiating sweating and blood flow responses. There has been no research on the role of group III/IV afferents on these fundamental exercise responses in humans. The investigators propose to isolate the role of group III/IV afferents on regulate airway resistance, sweating and blood flow responses to exercise in humans.

The Effects of Psilocybin in Healthy Volunteers: Psychological, Biochemical and Electrophysiological Biomarkers.

In this study, participants will received either psilocybin (the active ingredient found in certain mushrooms) or an inactive placebo (a look-alike tablet with no active drug). The psilocybin is supplied by Filament Health (Burnaby, British Columbia). After psilocybin ingestion, the body quickly converts it into psilocin, which is the form that produces the temporary psychological effects. Psilocin mainly works by interacting with serotonin receptors in the brain, especially a type called the 5-HT2A receptor. This study will be done in healthy volunteers using a single oral dose of 25 mg (one tablet by mouth), consistent with doses used in previous clinical research. The goal is to understand the biological, psychological, and high-density EEG (hd-EEG) changes that can happen after a one-time dose of psilocybin.

The Effects of Exogenous Ketones on Cognitive Function

The purpose of this study is to evaluate the acute effects of exogenous ketone monoester (KME) supplementation on cognitive function in three groups of adults aged 19-55 years: (1) obese, sedentary individuals; (2) lean, sedentary individuals; and (3) lean individuals who engage in regular physical activity (e.g., collegiate or amateur athletes). The main questions it aims to answer are to: * Assess the effects of acute KME supplementation versus placebo on cognitive, sensorimotor, and functional outcomes within groups. * Compare cognitive performance across the three groups. The primary outcome is cognitive performance assessed using the NIH Toolbox Cognition Battery. Secondary Outcomes include sensorimotor performance, measured using the Senaptec Sensory System, and driving performance, assessed with a driving simulator.

Targeted Lidocaine Infusion for Pain Reduction in Office Hysteroscopy

The goal of this study is to find out whether a small amount of lidocaine (a common local anesthetic) can reduce pain during office hysteroscopy - a procedure used to look inside the uterus. The study will compare lidocaine to saline (salt water) to see which one helps more with pain relief. Participants will: 1. Receive either lidocaine or saline gently applied inside the cervix right before the procedure 2. Undergo the hysteroscopy as planned 3. Be asked to rate their pain and satisfaction after the procedure Lidocaine is commonly and safely used in dental and gynecological procedures. Participation is voluntary, and the procedure itself will not change.

Premedication With N-acetylcysteine and Simethicone to Improve Mucosal Visualization in Elective Upper Endoscopy

The goal of this randomized, double-blind, placebo-controlled clinical trial is to assess whether the combination of N-acetylcysteine and simethicone improves mucosal visibility during upper gastrointestinal endoscopy in adults aged 18 to 99 years of both sexes, including both healthy individuals and those with non-bleeding gastrointestinal symptoms. The main questions this study aims to answer are: Does pre-endoscopy administration of N-acetylcysteine/simethicone improve mucosal visualization based on the Toronto Upper Gastrointestinal Cleanliness Score (TUGS)? Is this combination safe and well tolerated in this patient population? Researchers will compare patients receiving N-acetylcysteine (600 mg) and simethicone (100 mg) orally 20-60 minutes before the procedure with those receiving placebo (water) to determine if there is a significant improvement in TUGS scores. Participants will: Receive a single oral dose of either N-acetylcysteine/simethicone or placebo prior to endoscopy Undergo a routine upper GI endoscopy Have mucosal cleanliness evaluated using the TUGS scoring system Be monitored for any adverse events or intolerance

The Influences of Blood Flow Restriction on Leg Press

This study will investigate the use of different blood flow restriction cuffs during leg press exercise on arterial stiffness, muscle morphology, performance, and participant perception.